Object support for electron microscopes



i .Oct 17-,1944. J. HILLIER 5 OBJECT SUPPORT F'ORELECTRON MICROSCOPE vFiled Nov. 21, 1941 Zhmentoi' J3me) jaw/12f 1 (Ittorneg Patented on..17, 1944 OBJEUI SUPPORT FOR ELECTRON MICROSCOPES James Hillier,Colllnzswood, N. J., asslznor to Radio Corporation of America, acorporation of Delaware Application November 21, 1941, Serial No.419,896

2 Claims. (Cl. 250-495) This invention relates to an object support foruse in electron microscopes and more particularly to an object supportwhich permits the tilting of the object at different angles in order tosecure a stereoscopic picture.

The object support is in two parts, one of which is placed in themicroscope in a predeit at an angle. The second part, which carries theobject, is inserted in the hole in the first part and by the rotation ofthis second part in the first part the object can be tilted to variousangles and photographed successively in the various positions.

one object of the invention is to provide an improved object support forelectron microscopes.

Another object of the invention is to provide an object support whichwill permit the tilting of the object to difierent angles.

Another object of the invention is to provide an object support whichwill permit the taking of stereoscopic picture of the obiect.

Other and incidental objects of the invention will be apparent to thoseskilled in the art from a readins of the following specification and aninspection of the accompanying drawing in which Figure 1 is a top viewof-the object support; Figure 2 is a horizontal section through themiddle or Fe 1,

- Figures 3a and 3b show the appearance of an object at two positions orthe rotatable member,

' and Figure 2 is a view in elevation of one form of an electronmicroscope. The invention is not limited, nor intended to be limited, tothe precise form of the microscope shown, which is insorted merely toillustrate the relation of the object supporter the invention to otherelements of an electron microscope.

Referring first to Figures 1 and 2, the member it may be made of anyappropriate material such, for example, as brass, and is of sufficientlysmall size so that it may be mounted in an appropriate object carrier,such, for example, as that disclosed in my application Serial No.348,912, filed July 31, 1940, now Patent 2,272,843. This member I Gis'mounted in a predetermined position in the object carrier with theplane of its upper face perpendicular to the electron beam and inpredetermined orientation in relation to the instrument The member Illhas a cylindrical downward extension l4 having a hole therein tilted atan appropriate angle. In the min at termined position and has a holepassing through of the invention illustrated, the angle is of the orderof 6 but any suitable angle may be used according to the amount ofstereoscopic eilect desired. The member ii passes through the slantedhole in the member i4 and, although movable in the hole, is not so loosetherein as to become displaced in use. The tube It is pr0- v-lded withthe cap l2 which holds the object it, which may be mounted, for example,in a thin collodion film, in place at the end of the tube ll. As may beseen from Figure 4, the object support consisting of the members it andii and containing the object it is mounted in an evacuated envelope itin the path of a beam of electrons derived from a cathode H or otherappropriate source of electrons. The electron beam is focused on theobject to be viewed, passes through the object and is directed toward afiuorescent screen it or photographically sensitized plate it, so that amagnified electron image of i the object to be viewed may be obtained.The

general manner of operation of an electron microscope, and the relationof the object to be viewed to the other elements of the microscope arewell known to' those skilled in the art of electron microscopy. By wayof example, U. S. Patents 2,233,286 and 2,301,302 describe electronmicroscopes of the general type illustrated in I Figure e.

The top of the tube ii is provided with appropriate indicia and thesurface of the member in may he graduated as indicated at it to indicatethe orientation of the object. It will be apparent that the relativeposition of the index and gradnations may be reversed, and that thefineness oi the graduations is determined by the number of positions orthe object it may be desired to use. For example, if only the twoextreme positions of the objectare to be used, then only one pair ofmarks is necessary.

It will be noticed that the axis A-A of the electron beam passes throughthe center of the object plane and intersects the axis BB of the tube iiin the plane of the object I3. This arrangement facilitates therelocating of the same portion of the field after the tube II has beenrotated;

In using this device, the object is photographed in one position of thetube and then, if the .2 relation to its original position. In the formof the apparatus shown, it will be apparent that this will secure arelative tilt of the two images of the order of 12. The same field ofview is found and rephotographed.

If a smaller tilt is desired, this may be accomplished by rotating theobject holder H a correspondingly smaller amount. For example, Figure 3aand 3b show the type of eflect which would be produced if the objectbeing photographed were-cubica1 and the tube H were rotated only 60instead of 180.

The orientation of the member In is determined, in the form shown, byits two parallel sides, but other equivalent means may be provided, suchas index marks or a graduated scale.

[Ifhe photographs obtained must, of course, be mounted in properorientation to permit stereoscopic observation, as is usual in thepreparation of stereoscopic photographs.

I claim'as my invention:

1.An object holder for electron microscopes including a member adaptedto engage the microscope and rotatable in a plane perpendicular to theoptical axis to a plurality Of positions, and a. tubularobject-supporting member passing through the first member at an angle,with the axis of the tubular member intersecting the optical axis in theobject plane, said tubular memher being rotatable about its own axis,and both of said members carrying, indicia of their rotationalpositions.

2. An object holder for electron microscopes including amember adaptedto engage the microscope and rotatable in a plane perpendicular to theoptical axis to a plurality of positions, and a tubularobject-supporting member passing through the first member at an angle,with the axis of the tubular member intersecting the optical axis in theobject plane, said tubular mem- 20 her being rotatable about its ownaxis.

JAMES HILLIER.

